Display device

ABSTRACT

To improve the display quality of a display device, the display device includes a display section and a frame section surrounding a periphery of the display section. A substrate in the display device includes a conductor pattern constituting a circuit section and an insulating film serving as an organic film covering the conductor pattern. The insulating film extends to a peripheral edge of the substrate. A slit, which penetrates the insulating film in a thickness direction, is formed in a corner part of the insulating film. The slit is formed at a position not overlapping the circuit section.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.17/095,928, filed on Nov. 12, 2020, which, in turn, is a continuation ofU.S. patent application Ser. No. 16/191,865, filed on Nov. 15, 2018,which, in turn, is a continuation of U.S. patent application Ser. No.14/815,409 (now U.S. Pat. No. 10,310,309), filed on Jul. 31, 2015.Further, this application claims priority from Japanese PatentApplication No. 2014-163175 filed on Aug. 8, 2014, the entire contentsof which are hereby incorporated by reference into this application.

TECHNICAL FIELD OF THE INVENTION

The present invention relates to a technique effectively applied to adisplay device in which a pair of substrates is oppositely arranged anda display functional layer such as a liquid crystal layer is formedbetween the opposing substrates.

BACKGROUND OF THE INVENTION

There is a display device that seals the periphery of a displayfunctional layer such as a liquid crystal layer by arranging the displayfunctional layer between a pair of substrates oppositely arranged.Japanese Patent Application Laid-Open No. 2014-26199 (Patent Document 1)discusses forming a slit serving as a region where there is no blackmatrix around a sealing material, and blocking water entering a displayfunctional layer from an interface between the substrate and a blackmatrix.

A display device has a configuration in which a display functional layersuch as a liquid crystal layer is formed between a pair of substrates,the substrates are adhesively fixed to each other with a sealingmaterial in a sealing section around the display functional layer, sothat the display functional layer is protected.

An organic film composed of an organic material such as resin is formedas a protective film and a light shielding film, for example, insubstrates oppositely arranged. If the organic film is thus formed inthe substrate, water easily enters the display functional layer via theinside of the organic film or an interface between the organic film andthe substrate. When water enters the display functional layer, aconstituent material of the display functional layer changes in quality,so that a display functional characteristic may change. That is,entrance of water into the display functional layer causes a decrease indisplay quality.

A method for suppressing entrance of water into the display functionallayer includes a method for forming a slit in an organic film so as tosurround the periphery of a display region. The slit formed in theorganic film is formed by removing the organic film so as to bepenetrated in a thickness direction. In this case, a distance of anentrance path of water increases, so that entrance of water can bereduced.

If the slit is formed in the organic film so as to surround theperiphery of the display region, however, a function required for theorganic film cannot be exhibited in a portion where the slit is formed.If the slit is formed in the organic film formed as a protective film ofa circuit pattern, for example, the circuit pattern in a portionoverlapping the slit is not protected. Alternatively, if the slit isformed in the organic film formed as a light shielding film, a lightshielding member for suppressing leakage of light needs to be formed ina location other than the portion where the slit is formed so as tosuppress leakage of light from a portion where the slit is formed.

When measures taken when the function required for the organic film isnot exhibited are considered in the portion where the slit is formed,therefore, the area of a portion referred to as a so-called framesection or frame region serving as a non-display portion surrounding theperiphery of the display region is difficult to reduce.

SUMMARY OF THE INVENTION

The present invention is directed to providing a technique for improvingthe display quality of a display device.

A display device that is one aspect of the present invention includes adisplay section and a frame section surrounding a periphery of thedisplay section. Further, the display device includes a first substratehaving a first surface, a second substrate having a second surfaceopposing the first surface of the first substrate, a display functionallayer arranged in the display section between the first substrate andthe second substrate, and a circuit section provided in the framesection in the second substrate. Further, the second substrate includesa conductor pattern constituting the circuit section, and a firstorganic film covering the conductor pattern. Further, the first organicfilm extends to a peripheral edge of the second substrate. Further, afirst slit, which penetrates the first organic film in a thicknessdirection, is formed in a corner part of the first organic film.Further, the first slit is formed at a position not overlapping thecircuit section.

As another aspect of the present invention, the first organic filmincludes four corner parts, and the first slit is formed in each of thefour corner parts.

As another aspect of the present invention, a plurality of the firstslits are formed toward a peripheral edge of the display section from aperipheral edge of the first organic film in the corner part of thefirst organic film.

As another aspect of the present invention, the first slit is formed soas to draw a circular arc around a corner of the display section.

As another aspect of the present invention, the first organic filmincludes four corner parts, the first slit is formed in each of the fourcorner parts, and the first slit is not formed in sides among the fourcorner parts.

As another aspect of the present invention, both ends of the first slitrespectively communicate with edges of the first organic film.

As another aspect of the present invention, the first substrate includesa light shielding film composed of an organic material, the lightshielding film extends to a peripheral edge of the first substrate, asecond slit, which penetrates the light shielding film in a thicknessdirection, is formed in the frame section in the light shielding film,and a light shielding member composed of an inorganic material is formedin a portion where the second slit is formed.

As another aspect of the present invention, the second slit is formed soas to continuously surround the display section.

A display device that is another aspect of the present inventionincludes a display section and a frame section surrounding a peripheryof the display section. The display device includes a first substratehaving a first surface, a second substrate having a second surfaceopposing the first surface of the first substrate, a display functionallayer arranged in the display section between the first substrate andthe second substrate, and a circuit section provided in the framesection in the second substrate. Further, the first substrate includes alight shielding film composed of an organic material, and the secondsubstrate includes a conductor pattern constituting the circuit section.Further, the light shielding film extends to a peripheral edge of thefirst substrate. Further, a first slit, which penetrates the lightshielding film in a thickness direction, is formed in a corner part ofthe light shielding film. Further, a light shielding member is formed ata position overlapping the first slit in a thickness direction in thesecond substrate, and the light shielding member is formed at a positionnot overlapping the circuit section.

As another aspect of the present invention, the light shielding filmincludes four corner parts, and the first slit is formed in each of thefour corner parts.

As another aspect of the present invention, the light shielding filmincludes four corner parts, the first slit is formed in each of the fourcorner parts, and the first slit is not formed in sides among the fourcorner parts.

As another aspect of the present invention, both ends of the first slitformed in the light shielding film respectively communicate with edgesof the light shielding film.

BRIEF DESCRIPTIONS OF THE DRAWINGS

FIG. 1 is a plan view illustrating an example of a liquid crystaldisplay according to the present embodiment;

FIG. 2 is a sectional view along a line A-A illustrated in FIG. 1 ;

FIG. 3 is an enlarged sectional view of a portion B illustrated in FIG.2 ;

FIG. 4 is an enlarged sectional view of a portion C illustrated in FIG.2 ;

FIG. 5 is a plan view on the side of a front surface of a TFT substrateillustrated in FIGS. 3 and 4 ;

FIG. 6 is an enlarged plan view illustrating one of the four cornerparts of an organic film illustrated in FIG. 5 in an enlarged manner;

FIG. 7 is an enlarged sectional view taken along a line A-A illustratedin FIG. 6 ;

FIG. 8 is an enlarged plan view respectively illustrating a modificationexample of a slit illustrated in FIG. 6 ;

FIG. 9 is an enlarged plan view respectively illustrating anothermodification example of a slit illustrated in FIG. 6 ;

FIG. 10 is a plan view on the side of a back surface of a CF substrateillustrated in FIGS. 3 and 4 ;

FIG. 11 is a plan view on the side of a front surface of a substrateserving as a modification example of a TFT substrate illustrated in FIG.5 ;

FIG. 12 is an enlarged sectional view along a line A-A illustrated inFIG. 10 ;

FIG. 13 is an enlarged plan view illustrating one of the four cornerparts of a light shielding film illustrated in FIG. 10 in an enlargedmanner;

FIG. 14 is an enlarged plan view illustrating a part of a substrateopposing a region illustrated in FIG. 13 in an enlarged manner;

FIG. 15 is an enlarged plan view illustrating a modification example ofFIG. 11 ;

FIG. 16 is an enlarged plan view illustrating a part of a substrateopposing a region illustrated in FIG. 15 in an enlarged manner;

FIG. 17 is a plan view on the side of a back surface of a CF substrateserving as a modification example of FIG. 10 ; and

FIG. 18 is an enlarged sectional view taken along a line A-A illustratedin FIG. 17 .

DESCRIPTIONS OF THE PREFERRED EMBODIMENTS

Hereinafter, embodiments of the present invention will be described withreference to drawings. Note that the disclosures are provided by way ofexample, and any suitable variations easily conceived by a person withordinary skill in the art while pertaining to the gist of the inventionare of course included in the scope of the present invention. Further,in the drawings, widths, thicknesses and shapes of respective componentsmay be schematically illustrated in comparison with the embodiments forthe purpose of making the description more clearly understood, but theseare merely examples, and do not limit the interpretations of the presentinvention. Further, in the specification and drawings, elements whichare similar to those already mentioned with respect to previous drawingsare denoted by the same reference characters, and detailed descriptionsthereof will be suitably omitted.

In the following embodiment, a liquid crystal display including a liquidcrystal layer serving as a display functional layer will be specificallydescribed as an example of a display device. The liquid crystal displaydevice is also broadly classified into two categories, described below,depending on an application direction of an electric field for changingan orientation of liquid crystal molecules in the liquid crystal layerserving as the display functional layer. More specifically, the firstcategory is a so-called vertical electric field mode in which anelectric field is applied in a thickness direction (or an out-of-planedirection) of the liquid crystal display device. Examples of thevertical electric field mode include a Twisted Nematic (TN) mode and aVertical Alignment (VA) mode. The second category is a so-calledhorizontal electric field mode in which an electric field is applied ina planar direction (or an in-plane direction) of the liquid crystaldisplay device. Examples of the horizontal electric field mode includean In-Plane Switching (IPS) mode and a Fringe Field Switching (FFS) modeserving as one type of the IPS mode. While a technique described belowis applicable to both the vertical electric field mode and thehorizontal electric field mode. However, a display device in thehorizontal electric field mode will be described as an example in thepresent embodiment.

In the following embodiments, details of the frame section in the liquidcrystal display will be described with a plurality of examples after abasic configuration of the liquid crystal display is described.

<Basic Configuration of Liquid Crystal Display>

A basic configuration of a liquid crystal display will be firstdescribed. FIG. 1 is a plan view illustrating an example of the liquidcrystal display according to the present embodiment, and FIG. 2 is asectional view along a line A-A illustrated in FIG. 1 . FIG. 3 is anenlarged sectional view of a portion B illustrated in FIG. 2 . FIG. 4 isan enlarged sectional view of a portion C illustrated in FIG. 2 .

FIG. 1 is a plan view, where a display section DP is hatched and acontour of the display section DP is indicated by a two-dot and dashline to make a boundary between the display section DP and a framesection FL easy to see when seen in a plan view. In FIG. 1 , a contourof a seal SL provided in the frame section FL surrounding a periphery ofthe display section DP is indicated by a dotted line. In FIG. 1 , acontour of a circuit section CP provided between the display section DPand a peripheral edge of a substrate is indicated by a two-dot and dashline. FIG. 2 is a sectional view, where hatching is omitted forvisibility.

As illustrated in FIG. 1 , a display device LCD1 according to thepresent embodiment includes the display section DP serving as a displayregion where an image viewable from the outside is formed in response toan input signal. The display device LCD1 includes the frame section FLserving as a non-display region provided in a frame shape around thedisplay section DP when seen in a plan view. The display device LCD1includes a terminal section TM provided further outside the framesection FL when seen in a plan view. The terminal section TM includes aplurality of terminals TM1 for supplying an electric signal or a drivingvoltage to a plurality of elements for display formed in the displaysection DP and elements in the circuit sections CP provided in the framesection FL.

The frame section FL includes the circuit sections CP provided betweenthe display section DP and the peripheral edge of the substrate. In anexample illustrated in FIG. 1 , among sides 11 s 1, 11 s 2, 11 s 3, and11 s 4 of the substrate in the display device LDC1, the circuit sectionsCP are respectively provided between the side 11 s 3 and the displaysection DP and between the side 11 s 4 and the display section DP. In anexample illustrated in FIG. 4 , the circuit section CP is formed on theside of a substrate 12.

A conductor pattern constituting a driving circuit for forming an imagein the display section DP is formed in the circuit section CP. Theconductor pattern formed in the circuit section CP is electricallyconnected to the plurality of terminals TM1 formed in the terminalsection TM.

As schematically illustrated in FIG. 1 , the plurality of terminals TM1are connected to a flexible wiring board FPC. The flexible wiring boardFPC has a plurality of wirings formed in its resin film, for example,and can be freely deformed depending on a shape of an arrangementlocation. The plurality of terminals TM1 are electrically connected to adriving circuit DR1 and a control circuit CNT1 for image display via theflexible wiring board FPC. A semiconductor chip in which the drivingcircuit DR1 and the control circuit CNT1 are formed between the circuitsection CP and the plurality of terminals TM1 may be provided on thesubstrate 12 using a Chip on glass (COG) system.

The display device LCD1 has a configuration in which a liquid crystallayer is formed between a pair of substrates oppositely arranged. Morespecifically, as illustrated in FIG. 2 , the display device LCD1includes the substrate 11 on the side of a display surface, thesubstrate 12 positioned on the opposite side of the substrate 11, and aliquid crystal layer LCL (see FIG. 3 ) arranged between the substrate 11and the substrate 12.

The display device LCD1 includes the seal SL formed in the frame sectionFL around the display section DP where the liquid crystal layer LCL isformed when seen in a plan view, as illustrated in FIG. 1 . The seal SLis formed to continuously surround a periphery of the display sectionDP. The substrates 11 and 12 illustrated in FIG. 2 are adhesively fixedto each other with the seal SL illustrated in FIGS. 1 and 4 . The sealSL is thus provided around the display section DP, so that the liquidcrystal layer LCL formed in the display section DP and a part of theframe section FL can be sealed.

The substrate 11 illustrated in FIG. 1 has the side 11 s 1 extending inan X-direction, the side 11 s 2 opposing the side 11 s 1, the side 11 s3 extending in a Y-direction perpendicular to the X-direction, and theside 11 s 4 opposing the side 11 s 3 when seen in a plan view.Respective distances from the sides 11 s 1, 11 s 2, 11 s 3, and 11 s 4of the substrate 11 to the display section DP are substantially thesame.

The substrate 12 illustrated in FIG. 1 has a side 12 s 1 extending inthe X-direction, a side 12 s 2 opposing the side 12 s 1, a side 12 s 3extending in the Y-direction perpendicular to the X-direction, and aside 12 s 4 opposing the side 12 s 3 when seen in a plan view. In theexample illustrated in FIG. 1 , the terminal section TM is formed alongthe side 12 s 1 of the substrate 12. Therefore, a distance from the side12 s 1 of the substrate 12 to the display section DP is longer than adistance from each of the other sides 12 s 2, 12 s 3, and 12 s 4 of thesubstrate 1 to the display section DP. Respective distances from thesides 12 s 2, 12 s 3, and 12 s 4 of the substrate 12 to the displaysection DP are substantially the same.

As illustrated in FIG. 2 , a polarizing plate PL2 that polarizes lightgenerated from a light source LS is provided on the side of a backsurface 12 b of the substrate 12 in the display device LCD1. Thepolarizing plate PL2 is adhesively fixed to the substrate 12 via anadhesive layer. On the other hand, a polarizing plate PL1 is provided onthe side of a front surface 11 f of the substrate 11. The polarizingplate PL1 is fixed to the substrate 11 via an adhesive layer.

While basic components for forming a display image are illustrated inFIG. 2 , other components can be added to the components illustrated inFIG. 2 as modification examples. For example, a protective film or acover member may be attached to a front surface of the polarizing platePL1 as a protective layer for protecting the polarizing plate PL1 from aflaw or dirt. For example, the present invention can be applied to anexample in which an optical film such as a phase difference plate isaffixed to the polarizing plate PL1 and the polarizing plate PL2.Alternatively, a method for forming an optical film can be applied toeach of the substrates 11 and 12. As a modification example of FIG. 1 ,a semiconductor chip in which a driving circuit for supplying a pixelvoltage to pixel electrodes PE (see FIG. 3 ) may be mounted on a frontsurface 12 f of the substrate 12, for example.

As illustrated in FIG. 3 , the display device LCD1 includes theplurality of pixel electrodes PE arranged between the substrate 11 andthe substrate 12 and a common electrode CE arranged between thesubstrate 11 and the substrate 12. The display device LCD1 according tothe present embodiment is a display device in a horizontal electricfield mode, as described above. Thus, the plurality of pixel electrodesPE and the common electrode CE are respectively formed in the substrate12.

The substrate 12 illustrated in FIG. 3 includes a base material 12 stcomposed of a glass substrate, and a circuit for image display is mainlyformed in the base material 12 st. The circuit for image displayincludes the driving circuit formed in the circuit section CP (see FIG.1 ) and an active element such as a Thin-Film Transistor (TFT) formed inthe display section DP. The base material 12 st has the front surface 12f positioned on the side of the substrate 11 and the back surface 12 b(see FIG. 2 ) positioned on the opposite side thereof. The activeelement such as the TFT and the plurality of pixel electrodes PE areformed in a matrix shape on the side of the front surface 12 f of thesubstrate 12. A substrate on which the TFT is formed as the activeelement, e.g., the substrate 12, is referred to as a TFT substrate.

In an example illustrated in FIG. 3 , the display device LCD1 in thehorizontal electric field mode (specifically, a Fringe Field Switching(FFS) mode) is illustrated, as described above. Thus, the commonelectrode CE and the pixel electrodes PE are respectively formed on theside of the front surface 12 f of the substrate 12. The common electrodeCE is formed on the side of the front surface 12 f of the base material12 st included in the substrate 12, and is covered with an insulatingfilm OC2. The plurality of pixel electrodes PE are formed on a surface,on the side of the substrate 11, of the insulating film OC2 so as tooppose the common electrode CE via the insulating film OC2.

The substrate 12 has an oriented film AF2 covering the insulating filmOC2 and the plurality of pixel electrodes PE on the front surface 12 fserving as an interface contacting the liquid crystal layer LCL. Anoriented film AF1, which will be described below, and the oriented filmAF2 are resin films formed to align an initial orientation of a liquidcrystal included in the liquid crystal layer LCL, and are composed ofpolyimide resin, for example.

The substrate 11 illustrated in FIG. 3 is a substrate in which a colorfilter CF forming a color display image is formed on a base material 11st composed of a glass substrate, and has the front surface 11 f on theside of the display surface and a back surface 11 b (see FIG. 2 )positioned on the opposite side of the front surface 11 f. Whendistinguished from the above-described TFT substrate, a substrate inwhich a color filter CF is formed, for example, the substrate 11 isreferred to as a color filter (CF) substrate or an opposite substratebecause it opposes the TFT substrate via a liquid crystal layer. As amodification example of FIG. 3 , a configuration in which the colorfilter CF is provided in the TFT substrate may be adopted.

The substrate 11 has the color filter CF, configured by periodicallyarranging color filter pixels CFr, CFg, and CFb in three colors, i.e.,red (R), green (G), and blue (B) on one surface of the base material 11st composed of the glass substrate, for example, formed therein. In acolor display device, sub-pixels in three colors, i.e., red (R), green(G), and blue (B), for example, as one set, constitute one pixel (alsoreferred to as one pixel). The plurality of color filter pixels CFr,CFg, and CFb in the substrate 11 are arranged at positions respectivelyopposing sub-pixels having the pixel electrodes PE formed in thesubstrate 12.

Light shielding films BM are respectively formed in boundaries among thecolor filter pixels CFr, CFg, and CFb in the colors. The light shieldingfilm BM is referred to as a black matrix, and is composed of blackresin, for example. The light shielding films BM are formed in a latticeshape when seen in a plan view. In other words, the substrate 11 has thecolor filter pixels CFr, CFg, and CFb in the colors formed among thelight shielding films BM formed in a lattice shape.

In the present application, a region described as the display section DPor the display region is defined as a region inside the frame sectionFL. The frame section FL is a region covered with the light shieldingfilms BM for blocking light irradiated from the light source LSillustrated in FIG. 2 . While the light shielding films BM are alsoformed in the display section DP, in the display section DP, a pluralityof openings are formed in the light shielding films BM, and the colorfilter CF is formed in the openings. Therefore, among the plurality ofopenings in which the color filter CF is formed, an end portion of theopening formed closest to the peripheral edge of the substrate 11 isdefined as a boundary between the display section DP and the framesection FL. However, a slit for suppressing entrance of water may beformed in the light shielding film BM, as described below. The openingformed for the purpose of suppressing entrance of water is distinguishedfrom the above-described opening in that the color filter CF is notformed.

The substrate 11 includes a resin film OC1 covering the color filter CF.The light shielding films BM are respectively formed at boundaries amongthe color filter pixels CFr, CFg, and CFb in the colors. Thus, an innerside surface of the color filter CF becomes an irregular surface. Theresin film OC1 functions as a flattening film for flatteningirregularities on the inner side surface of the color filter CF.Alternatively, the resin film OC1 functions as a protective film forpreventing impurities from being diffused toward the liquid crystallayer from the color filter CF. A resin material for the resin film OC1can be cured by containing a component, which is cured by applyingenergy, e.g., a thermosetting resin component or a light curing resincomponent. The resin film OC1 is preferably formed of an organicmaterial such as resin from a viewpoint of flattening the irregularitieson the inner side surface of the color filter CF.

The substrate 11 includes the oriented film AF1 covering the resin filmOC1 on the back surface 11 b serving as its interface contacting theliquid crystal layer LCL. This oriented film AF1 is a resin film formedto align an initial orientation of a liquid crystal included in theliquid crystal layer LCL, and is composed of polyimide resin, forexample. In the example illustrated in FIG. 4 , a member FS forsuppressing expansion of the oriented film AF1 is provided on the sideof a peripheral edge of the display section DP. The member FS functionsas a damping member for suppressing wide covering of the frame sectionFL with the oriented film AF1 when the oriented film AF1 is formed onthe back surface 11 b of the substrate 11 in a process for manufacturingthe display device LCD1. Therefore, the member FS is formed so as toproject toward the back surface 11 b of the substrate 11.

The liquid crystal layer LCL, which forms a display image by applying adisplay voltage between the pixel electrodes PE and the common electrodeCE, is provided between the substrate 11 and the substrate 12. Theliquid crystal layer LCL modulates light that passes therethroughdepending on a state of an applied electric field.

As illustrated in FIG. 4 , the seal SL arranged to surround the liquidcrystal layer LCL is composed of a sealing material SLp. The liquidcrystal layer LCL is sealed into a region surrounded by the sealingmaterial SLp. That is, the sealing material SLp functions as a sealingmaterial for preventing the liquid crystal layer LCL from leaking out.The sealing material SLp closely adheres to each of the back surface 11b of the substrate 11 and the front surface 12 f of the substrate 12.The substrate 11 and the substrate 12 are thus adhesively fixed to eachother via the sealing material SLp. That is, the sealing material SLpfunctions as an adhesive member for adhesively fixing the substrate 11and the substrate 12.

The thickness of the liquid crystal layer LCL illustrated in FIGS. 3 and4 is significantly smaller than the thicknesses of the substrates 11 and12. For example, the thickness of the liquid crystal layer LCL isapproximately 0.1% to 10% of the thicknesses of the substrates 11 and12. In the example illustrated in FIGS. 3 and 4 , the thickness of theliquid crystal layer LCL is approximately 4 μm, for example.

In the present embodiment, the frame section FL includes the circuitsection CP provided between the display section DP and the peripheraledge of the substrate, as illustrated in FIGS. 1 and 4 . A conductorpattern CDP is formed in the circuit section CP. The conductor patternis a conductor patterned so as to constitute a circuit, and is formed ofa single metal such as copper (Cu) or aluminum (Al) or its alloy, forexample. When the circuit is thus formed by the conductor pattern CDP,an insulating film OC2 is preferably formed so as to cover the conductorpattern CDP from a viewpoint of suppressing damage of the conductorpattern CDP. At least an outermost surface of the insulating film OC2 ispreferably formed of an organic film such as a resin film from aviewpoint of forming the insulating film OC2 so as to reliably cover theconductor pattern CDP. Alternatively, the insulating film OC2 may be astacked film obtained by stacking an inorganic insulating film and anorganic insulating film in this order from the base material 12 st.Irregularities on the surface of the insulating film OC2 can be reducedand flattened by forming the organic insulating film so as to cover theinorganic insulating film.

A method for displaying a color image by the display device LCD1illustrated in FIG. 3 is as follows, for example. More specifically,light emitted from the light source LS is filtered by a polarizing platePL2, and light passing through the polarizing plate PL2 is incident onthe liquid crystal layer LCL. The light, which has been incident on theliquid crystal layer LCL, is propagated in a thickness direction of theliquid crystal layer LCL (i.e., a direction toward the substrate 11 fromthe substrate 12) by changing a polarization state depending onrefractive index anisotropy (i.e., birefringence) of a liquid crystal,and is emitted from the substrate 11. At this time, liquid crystalorientation is controlled by an electric field formed by applying avoltage to the pixel electrodes PE and the common electrode CE. Theliquid crystal layer LCL functions as an optical shutter. Morespecifically, in the liquid crystal layer LCL, light transmittance canbe controlled for each sub-pixel. The light, which has reached thesubstrate 11, is subjected to color filtering processing (i.e.,processing for absorbing light having a wavelength other than apredetermined wavelength) in the color filter CF formed in the substrate11, and is emitted from the front surface 11 f. The light emitted fromthe front surface 11 f reaches a viewer VW via the polarizing plate PL1.

<Details-1 of Frame Section>

Details of the frame section FL will be described below. In thissection, a technique for suppressing entrance of water from theperiphery of an organic film formed on the side of the substrate 12 outof the substrates 11 and 12 illustrated in FIG. 4 will be described.FIG. 5 is a plan view on the side of a front surface of the TFTsubstrate illustrated in FIGS. 3 and 4 . FIG. 5 illustrates a statewhere the substrate 11 and the seal SL illustrated in FIG. 4 are removedso as to make a structure on the side of the substrate 12 illustrated inFIG. 1 easy to see. In FIG. 5 , the display section DP, the circuitsections CP, and each of four corner parts OCc1, OCc2, OCc3, and OCc4 ofthe insulating film OC2 are respectively surrounded by two-dot and dashlines.

In recent years, a technique for reducing the width of the frame sectionFL in the display device to increase a ratio of the effective displayarea of the display device has been required form a viewpoint ofimproving designability or a viewpoint of lighter weight. When the widthof the frame section FL is reduced, however, a distance from an outeredge of the substrate to the display section DP is reduced. If waterenters the substrate from the outer edge of the substrate, therefore,the water easily reaches the display section DP. Particularly if theorganic film formed on the side of opposing surfaces of the pair ofsubstrates extends to the outer edge of the substrate, water easilyenters the display section DP through an adhesive interface between theorganic film and the substrate or the inside of the organic film. Whenwater enters the display section DP, a constituent material of theliquid crystal layer LCL formed in the display section DP changes inquality, so that a display functional characteristic may change. Theinsulating film OC2 serving as the organic film formed in the substrate12 extends toward the peripheral edge of the substrate 12, asillustrated in FIG. 5 , for example.

A method for suppressing entrance of water into the display section DPincludes a method for forming a slit serving as an opening, whichpenetrates an organic film, so as to surround a periphery of the displaysection DP. When the slit is formed to penetrate the organic film in athickness direction, a water entrance path is blocked hallway to therebyinhibit entrance of water. Even if the width of the frame section FL isreduced, therefore, a time elapsed until water enters the displaysection DP can be extended.

If the circuit section CP is provided between the display section DP andthe peripheral edge of the substrate, as illustrated in FIG. 1 , aposition where a slit is formed becomes a problem. More specifically,when a slit is formed in the insulating film OC2 serving as an organicfilm in the frame section FL illustrated in FIG. 4 , a part of theconductor pattern CDP is exposed in the slit. In a portion exposed fromthe insulating film OC2, the conductor pattern CDP is not protected.Therefore, the entire conductor pattern CDP is preferably covered withthe insulating film OC2 without a slit being formed in the circuitsection CP from a viewpoint of reliably protecting the conductor patternCDP.

On the other hand, for the entire conductor pattern CDP to be coveredwith the insulating film OC2, a slit needs to be formed in a locationother than the circuit section CP. If a formation region of the slit isprovided between the circuit section CP and the peripheral edge of thesubstrate, however, the width of the frame section FL increases.

The inventors of the present application have further examined aphenomenon where a display functional characteristic changes becausewater enters the display section DP from the outer edge of thesubstrate. According to the examination by the inventors of the presentapplication, the change in the display functional characteristic due tothe entrance of water is first actualized in corner parts of the displaysection DP. An example of the change in the display functionalcharacteristic includes a phenomenon where nonuniformity in display isvisualized. However, the nonuniformity in display is first visualized incorner parts of an effective display region constituting a square.

Thus, the change in the display functional characteristic is firstactualized in the corner parts of the display section DP from thefollowing reason. That is, distances of each of the corner parts of thedisplay section DP to two of the four sides of the substrate are short.Thus, an amount of water entering the corner part is relatively largerthan that entering the side positioned between the adjacent cornerparts. In the example illustrated in FIG. 5 , for example, the cornerpart DPc1 among the four corner parts of the display section DP isrequired to consider entrance of water from the side 12 s 3 of thesubstrate 12 in addition to entrance of water from the side 12 s 2 ofthe substrate 12. The corner part DPc2 is required to consider entranceof water from the side 12 s 4 of the substrate 12 in addition toentrance of water from the side 12 s 2 of the substrate 12. Respectivedistances of the corner parts DPc3 and DPc4 to the side 12 s 1 of thesubstrate 12 are long, so that respective amounts of water entering thecorner parts DPc3 and DPc4 are smaller than those entering the cornerparts DPc1 and DPc2. However, the relatively larger amount of waterenters the corner parts DPc3 and DPc4 than that entering the sidebetween the corner parts.

A period during which the display quality of the display device can bemaintained can be extended by reducing an amount of water entering thedisplay section DP toward the corner part of the display section DP ifthe fact that the change in the display functional characteristic isfirst actualized in the corner part of the display section DP is paidattention to, as described above. In other words, the life of a productcan be extended.

A slit need not be formed so as to continuously surround a periphery ofthe display section DP if the fact that the amount of water entering thecorner part of the display section DP is reduced is paid attention to.For example, a slit SLT may be selectively formed in the corner parts ofthe insulating film OC2 serving as an organic film covering the frontsurface 12 f of the substrate 12, as illustrated in FIG. 5 .

In an example illustrated in FIG. 5 , the slit SLT is formed in each ofthe corner parts OCc1, OCc2, OCc3, and OCc4 of the insulating film OC2.The slits SLT are not connected to, but independent of one another.

The corner parts OCc1, OCc2, OCc3, and OCc4 of the insulating film OC2are defined as follows. More specifically, the corner part OCc1 is aregion surrounded by extensions of a contour line of the display sectionDP, the side OCs2 of the insulating film OC2, and the side OCc3 of theinsulating film OC2. The corner part OCc2 is a region surrounded byextensions of the contour line of the display section DP, the side OCs2of the insulating film OC2, and the side OCS4 of the insulating filmOC2. The corner part OCc3 is a region surrounded by extensions of thecontour line of the display section DP, the side OCs1 of a terminationportion of the organic film, and the side OCs3 of the insulating filmOC2. The corner part OCc4 is a region surrounded by extensions of thecontour line of the display section DP, the side OCs1 of the terminationportion of the organic film, and the side OCs4 of the insulating filmOC2.

In the example illustrated in FIG. 5 , the insulating film OC2 servingas an organic film covering the front surface 12 f of the substrate 12has the side OCs1 extending in the X-direction, the side OCs2 opposingthe side OCs1, the side OCs3 extending in the Y-direction perpendicularto the X-direction, and the side OCs4 opposing the side OCs3 when seenin a plan view. In the example illustrated in FIG. 5 , the terminalsection TM is formed along the side OCs1 of the insulating film OC2.Thus, the side OCs1 of the insulating film OC2 exists between the side12 s 1 of the substrate 12 and the display section DP. On the otherhand, the sides OCs2, OCs3, and OCS4 of the insulating film OC2respectively match the sides 12 s 2, 12 s 3, and 12 s 4 of the substrate12 when seen in a plan view.

As illustrated in FIG. 5 , the slit SLT is formed in each of the cornerparts OCc1, OCc2, OCc3, and OCc4 of the insulating film OC2, so thatwater entering the display section DP toward the corner part of thedisplay section DP can be reduced. The plurality of slits SLT areseparated from one another, so that the slit SLT is not formed in thecircuit section CP. Thus, the entire conductor pattern CDP (see FIG. 4 )formed in the circuit section CP is covered with the insulating film OC2serving as a protective film. Therefore, the conductor pattern CDPformed in the circuit section CP can be reliably protected.

In the present embodiment, the slit SLT is not formed between thecircuit section CP and the side 12 s 3 of the substrate 12 and betweenthe circuit section CP and the side 12 s 4 of the substrate 12. In otherwords, the slit SLT is not formed between the corner parts OCc1 and OCc3of the insulating film OC2 and between the corner parts OCc2 and OCc4 ofthe insulating film OC2. Therefore, a space required to form the circuitsection CP has only to be ensured as a distance between the peripheraledge of the substrate 12 and the display region, so that the width ofthe frame section FL can be reduced.

Details of the slit SLT illustrated in FIG. 5 formed for the purpose ofsuppressing entrance of water will be described below. FIG. 6 is anenlarged plan view illustrating one of the four corner parts of anorganic film illustrated in FIG. 5 in an enlarged manner. FIG. 7 is anenlarged sectional view taken along a line A-A illustrated in FIG. 6 .

FIG. 6 illustrates the corner part OCc3 and its vicinities as arepresentative example of the corner parts OCc1, OCc2, OCc3, and OCc4 ofthe insulating film OC2 illustrated in FIG. 5 in an enlarged manner.While illustration in an enlarged plan view of the other corner partsOCc1, OCc2, and OCc4 is omitted, a similar slit SLT to that in thecorner part OCc3 is formed.

In an example illustrated in FIG. 6 , a plurality of slits SLT1 servingas openings formed so as to remove a part of the insulating film OC2 areformed in the corner part OCc3 of the insulating film OC2. Each of theplurality of slits SLT1 is formed to penetrate the insulating film OC2in a thickness direction, as illustrated in FIG. 7 . Thus, the slitsSLT1, which penetrate the insulating film OC2 serving as an organic filmin the thickness direction, are formed, to divide an entrance path ofwater. Therefore, even if water enters the display section DP from aperipheral edge of the insulating film OC2, the water does not reach thecorner part DPc3 of the display section DP unless the water bypasses theslits SLT1. Therefore, a time elapsed until the water reaches thedisplay section DP can be extended.

As described above, the insulating film OC2 may be a stacked filmobtained by stacking an inorganic insulating film and an organicinsulating film in this order from the base material 12 st. Theabove-described water enters the display section DP via an adhesiveinterface between the organic insulating film and the inorganicinsulating film, or via the inside of the organic insulating film. Ifthe insulating film OC2 is a stacked film of the inorganic insulatingfilm and the organic insulating film, therefore, the slits SLT1 may beformed so as to penetrate the organic insulating film of the insulatingfilm OC2 in the thickness direction.

In the example illustrated in FIG. 6 , the four slits SLT1 are arrangedtoward the corner part DPc3 of the display section DP from a cornerserving as an intersection between the sides OCs1 and OCs3 of theinsulating film OC2. In other words, the plurality of slits SLT1 areformed toward the peripheral edge of the display section DP from theperipheral edge of the insulating film OC2 in the corner part OCc3 ofthe insulating film OC2.

However, the number of the slits SLT1 provided in the one corner partOCc3 is not limited to four, but there are various modificationexamples. For example, the effect of dividing the entrance path of waterby the slits SLT1 is obtained if at least one of the slits SLT1 isarranged between a corner at the peripheral edge of the insulating filmOC2 and the corner part DPc3 of the display section DP. The plurality ofslits SLT1 are preferably arranged between the corner at the peripheraledge of the insulating film OC2 and the corner part DPc3 of the displaysection DP, as illustrated in FIG. 6 , from a viewpoint of more reliablysuppressing the entrance of water.

If the plurality of slits SLT1 are formed, the opening width of each ofthe slits SLT1 can be set to approximately 10 μm to 100 μm, for example.Separation distances among the plurality of slits SLT1 can be set toapproximately 30 μm to 100 μm, for example, although they can bedetermined depending on the number of the slits SLT1 to be arranged anda space of the corner part OCc3. In this case, the entrance of water canbe effectively suppressed by determining the number of the slits SLT1and the opening width of each of the slits SLT1 such that the sum of theopening widths of the plurality of slits SLT1 is approximately 140 μm to300 μm.

In the example illustrated in FIG. 6 , the plurality of slits SLT1 areformed to draw a circular arc around the corner part DPc3 of the displaysection DP. When each of the plurality of slits SLT1 is thus formed todraw a circular arc, a bypass distance during entrance of water can bemade longer than when the slits SLT1 are linearly formed.

As a modification example of the slits SLT1 illustrated in FIG. 6 , thefollowing example will be described below. FIGS. 8 and 9 are enlargedplan views respectively illustrating the modification examples of theslits SLT1 illustrated in FIG. 6 . A plurality of slits SLT2 illustratedin FIG. 8 and a plurality of slits SLT3 illustrated in FIG. 9 differfrom the plurality of slits SLT1 illustrated in FIG. 6 in that both endsof an opening formed in the insulating film OC2 respectively communicatewith edges of the insulating film OC2.

In the modification example illustrated in FIG. 8 , each of theplurality of slits SLT2 is connected to a pullout portion extending tothe edge of the insulating film OC2. The pullout portion is an openingformed so as to penetrate the insulating film OC2 serving as an organicfilm in the thickness direction, like the slits SLT1 described withreference to FIG. 7 . Therefore, both ends of each of the slits SLT2respectively communicate with the edges of the insulating film OC2.

In the modification example illustrated in FIG. 9 , each of theplurality of slits SLT3 has a pullout portion extending to the edge ofthe insulating film OC2. The pullout portion is an opening formed so asto penetrate the insulating film OC2 serving as an organic film in thethickness direction, like the slits SLT1 described with reference toFIG. 7 . Therefore, both ends of each of the plurality of slits SLT3respectively communicate with the edges of the insulating film OC2.

If both ends of the opening respectively communicate with the edges ofthe insulating film OC2, like the slits SLT2 and SLT3, a path wherewater, having entered the corner part OCc3 of the insulating film OC2,bypasses can be blocked. Therefore, water having entered a regionsurrounded by the slits SLT2 or the slits SLT3 and the edges of theinsulating film OC2, can be prevented from reaching the display sectionDP.

While an example in which the slit SLT is formed in only each of thefour corner parts OCc1, OCc2, OCc3, and OCc4 of the insulating film OC2is illustrated in FIG. 5 , various modification examples can be appliedunless the circuit section CP and the slit SLT do not overlap each otherin the thickness direction. In the example illustrated in FIG. 5 , forexample, the circuit section CP is not formed in a region (i.e., a side)between the corner parts OCc1 and OCc2 of the insulating film OC2.Therefore, the slit SLT formed in the corner part OCc1 and the slit SLTformed in the corner part OCc2 may communicate with each other. In thiscase, water entering the side OCs2 of the insulating film OC2 can beprevented from reaching the display section DP.

If the wirings for connecting the terminals TM1 and the circuit sectionsCP need to be respectively formed in the corner parts OCc3 and OCc4,arranged on the side of the terminal section TM, among the four cornerparts OCc1, OCc2, OCc3, and OCc4 of the insulating film OC2, openingwidths of the slits SLT formed in the corner parts OCc3 and OCc4 may besmaller than opening widths of the slits SLT formed in the corner partsOCc1 and OCc2. Alternatively, there is also a modification example inwhich if an arrangement space of the slit SLT is difficult to be ensuredin the corner parts OCc3 and OCc4, the slit SLT is not arranged in thecorner parts OCc3 and OCc4 among the four corner parts OCc1, OCc2, OCc3,and OCc4 of the insulating film OC2.

<Details-2 of Frame Section>

As an embodiment other than the display device LCD1 described withreference to FIGS. 5 to 9 , a technique for suppressing entrance ofwater from the periphery of an organic film formed on the side of thesubstrate 11 out of the substrates 11 and 12 illustrated in FIG. 4 willbe described below. FIG. 10 is a plan view on the side of a back surfaceof the CF substrate illustrated in FIGS. 3 and 4. FIG. 11 is a plan viewon the side of a front surface of a substrate serving as a modificationexample of the TFT substrate illustrated in FIG. 5 . FIG. 12 is anenlarged sectional view along a line A-A illustrated in FIG. 10 . Whilea resin film OC1 covering a light shielding film BM is formed, asillustrated in FIGS. 3 and 4 , on a back surface 11 b of the substrate11, FIG. 10 illustrates a state where the resin film OC1 is removed soas to clarify a positional relationship of slits SLT formed in the lightshielding film BM.

As described above, the light shielding film BM and the resin film OC1covering the light shielding film BM illustrated in FIGS. 3 and 4 areorganic films each composed of an organic material. The organic film ismore easily processed than an inorganic film. The organic film can beformed by a method for applying a liquid-like or paste-like material andthen curing the applied material, so that the organic film more easilyflattens a film formation surface than the inorganic film.

If the light shielding film BM and the resin film OC1 each serving as anorganic film extend toward a peripheral edge of the substrate 11, asillustrated in FIG. 4 , however, water easily enters the display sectionDP via an adhesive interface between the organic film and the substrateor the inside of the organic film. As described in the above-describedsection <Details-1 of Frame Section>, when water enters the displaysection DP, a constituent material of the liquid crystal layer LCLformed in the display section DP changes in quality, so that a displayfunctional characteristic may change.

If the slit SLT is formed in the light shielding film BM serving as anorganic film as a method for suppressing entrance of water into thedisplay section DP, a light shielding member for preventing light fromleaking out needs to be provided at a position where the slit SLT isformed. The light shielding film BM is a member for blocking lightirradiated from the light source LS illustrated in FIG. 2 . Thus, if theslit SLT is formed in the light shielding film BM, a light shieldingmember serving as a light shielding pattern corresponding to a shape ofthe slit SLT needs to be formed at a position overlapping the slit SLTin a thickness direction. If the slit SLT is formed in the substrate 11,therefore, a method for forming the light shielding member in thesubstrate 12 opposing the substrate 11 can be considered.

If a conductor pattern CDP (see FIG. 4 ) constituting the circuitsection CP is formed in the substrate 12, as described above, however,the light shielding member needs to be formed so as to avoid theconductor pattern CDP. Thus, a slit SLT needs to be formed in a locationother than a circuit section CP; however, if a slit formation region isprovided between the circuit section CP and a peripheral edge of thesubstrate, the width of a frame section FL increases.

Therefore, the inventors of the present application have applied thetechnique described in the above-described section <Details-1 of FrameSection> to find out a technique for reducing the width of the framesection FL and suppressing entrance of water in the substrate 11. Morespecifically, when an amount of water entering a corner part of thedisplay section DP is reduced, as described above, a period elapseduntil a display functional characteristic changes can be lengthened.Therefore, a slit SLT need not be formed to continuously surround aperiphery of the display section DP. As illustrated in FIG. 10 , forexample, the slit SLT may be selectively formed in a corner part of thelight shielding film BM serving as an organic film formed on the side ofthe back surface 11 b of the substrate 11.

In an example illustrated in FIG. 10 , the slit SLT is formed in each ofcorner parts BMc1, BMc2, BMc3, and BMc4 of the light shielding film BM.The slits SLT are not connected to, but independent of one another. Eachof the plurality of slits SLT is an opening formed so as to penetratethe light shielding film BM in the thickness direction, as illustratedin FIG. 12 . The slit SLT may be formed so as to penetrate the resinfilm OC1. However, the slit SLT may be provided only in the lightshielding film BM, and the slit SLT in the light shielding film BM maybe covered with the resin film OC. As illustrated in FIG. 11 , the lightshielding member BP serving as a light shielding pattern correspondingto a shape of the slit SLT illustrated in FIG. 10 is formed at aposition opposing the slit SLT.

As illustrated in FIG. 12 , the light shielding member BP is formed at aposition overlapping the slit SLT in the thickness direction. The lightshielding member BP is formed in a shape similar to an opening shape ofthe slit SLT, and the area of the light shielding member BP is largerthan the opening area of the slit SLT. Thus, light irradiated from thelight source LS illustrated in FIG. 2 is blocked by the light shieldingmember BP, so that leakage of light out of the slit SLT formed in thelight shielding film BM can be suppressed. While the light shieldingmember BP is the same material as a metal forming a wiring on the TFTsubstrate, and is formed integrally with a part of the wiring or apartfrom the wiring, the light shielding member BP may be an organic filmcontaining a black pigment or a material different from the metalforming the wiring, e.g., chromium (Cr) or a chromium oxide.

The corner parts BMc1, BMc2, BMc3, and BMc4 of the light shielding filmBM illustrated in FIG. 10 are defined as follows. More specifically, thecorner part BMc1 is a region surrounded by extensions of a contour lineof the display section DP, the side BMs2 of the light shielding film BM,and the side BMs3 of the light shielding film BM. The corner part BMc2is a region surrounded by extensions of the contour line of the displaysection DP, the side BMs2 of the light shielding film BM, and the sideBMs4 of the light shielding film BM. The corner part BMc3 is a regionsurrounded by extensions of the contour line of the display section DP,the side BMs1 of the light shielding film BM, and the side BMs3 of thelight shielding film BM. The corner part BMc4 is a region surrounded byextensions of the contour line of the display section DP, the side BMs1of the light shielding film BM, and the side BMs4 of the light shieldingfilm BM.

In the example illustrated in FIG. 10 , the light shielding film BMserving as an organic film covering the front surface 12 f of thesubstrate 12 has a side BMs1 extending in an X-direction, a side BMs2opposing the side BMs1, a side BMs3 extending in a Y-directionperpendicular to the X-direction, and a side BMs4 opposing the side BMs3when seen in a plan view. In the example illustrated in FIG. 10 , theterminal section TM (see FIG. 11 ) is not formed in the substrate 11.Therefore, the sides BMs1, BMs2, BMs3, and BMs4 of the light shieldingfilm BM respectively match the sides 11 s 1, 11 s 2, 11 s 3, and 11 s 4of the substrate 11 when seen in a plan view.

As illustrated in FIG. 10 , when slits SLT are respectively formed inthe corner parts BMc1, BMc2, BMc3, and BMc4 of the light shielding filmBM, water entering the display section DP toward the corner part of thedisplay section DP can be reduced. The plurality of slits SLT areseparated from one another, so that the light shielding member BP formedso as to correspond to the slit SLT (see FIG. 10 ), as illustrated inFIG. 11 , is not formed in the circuit section CP. The light shieldingmember BP is not formed between the circuit section CP and the sides 12s 3 of the substrate 12, and between the circuit section CP and the side12 s 4 of the substrate 12. In other words, the slit SLT is not formedbetween the corner parts BMc1 and BMc3 and between the corner parts BMc2and BMc4 of the light shielding film BM illustrated in FIG. 10 .Therefore, the width of the frame section FL can be reduced.

Details of the slits SLT illustrated in FIG. 10 will be described below.FIG. 13 is an enlarged plan view illustrating one of the four cornerparts of the light shielding film BM illustrated in FIG. 10 in anenlarged manner. FIG. 14 is an enlarged plan view illustrating a part ofa substrate opposing a region illustrated in FIG. 13 in an enlargedmanner.

In FIG. 13 , as a representative example of the corner parts BMc1, BMc2,BMc3, and BMc4 of the light shielding film BM illustrated in FIG. 10 ,the corner part BMc3 and its vicinities are illustrated in an enlargedmanner. While illustration in an enlarged plan view of the other cornerparts BMc1, BMc2, and BMc4 is omitted, a similar slit SLT to that in thecorner part BMc3 is formed.

In an example illustrated in FIG. 13 , the slit SLT serving as anopening formed so as to remove a part of the light shielding film BM isformed in the corner part BMc3 in the light shielding film BM. The slitSLT4 is formed so as to penetrate the light shielding film BM in thethickness direction, as illustrated in FIG. 12 . Thus, the slit SLT4,which penetrates the light shielding film BM serving as an organic filmin the thickness direction, is formed, to divide an entrance path ofwater. Even if water enters the display section DP from the peripheraledge of the light shielding film BM, therefore, the water does not reachthe corner part DPc3 of the display section DP unless it bypasses theslit SLT4. Thus, a time elapsed until the water reaches the displaysection DP can be extended.

As illustrated in FIG. 12 , in a case where the light shielding film BMis covered with the resin film OC1 serving as an organic film, if theslit SLT is formed so as to penetrate at least the light shielding filmBM, water entering the display section DP via an adhesive interfacebetween the light shielding film BM and a base material 11 st or via theinside of the light shielding film BM can be reduced even when the resinfilm OC1 is embedded in the slit SLT. If the slit SLT is formed so as topenetrate the resin film OC1 in addition to the light shielding film BM,an entrance path of water via the inside of the resin film OC1 can alsobe blocked.

In the example illustrated in FIG. 10 , one slit SLT is formed in eachof the corner parts BMc1, BMc2, BMc3, and BMc4 of the light shieldingfilm BM. As a modification example of FIGS. 10 to 14 , a plurality ofslits SLT can also be arranged at one corner part, like the slits SLT1described with reference to FIG. 6 . However, the number of slits SLT ispreferably small from a viewpoint of suppressing leakage of light in theslits SLT.

If one slit SLT4 is formed, as illustrated in FIG. 13 , the openingwidth of the slit SLT4 can be set to approximately 30 μm to 100 μm, forexample. If the plurality of slits SLT are arranged, which are notillustrated, the respective opening widths of the plurality of slits SLTcan also be set to smaller values, e.g., approximately 10 μm to 15 μm.

In the example illustrated in FIG. 13 , the slit SLT4 forms an L shapealong a contour of the corner part BMc3 of the light shielding film BM.When the slit SLT4 is thus formed to draw a letter L, a bypass distanceduring entrance of water can be made longer than when the slit SLT4 islinearly formed. A modification example of the slit SLT4 illustrated inFIG. 13 may be formed to draw a circular arc around the corner part DPc3of the display section DP, like the slit SLT1 illustrated in FIG. 6 .

As a modification example of the slit SLT4 illustrated in FIG. 13 , thefollowing example will be described below. FIG. 15 is an enlarged planview illustrating a modification example of the slit SLT4 illustrated inFIG. 13 . FIG. 16 is an enlarged plan view illustrating a part of asubstrate opposing a region illustrated in FIG. 15 in an enlargedmanner. A slit SLT5 illustrated in FIG. 15 differs from the slit SLT4illustrated in FIG. 13 in that both ends of an opening formed in thelight shielding film BM respectively communicate with edges of the lightshielding film BM. A light shielding member BP2 illustrated in FIG. 16differs from the light shielding member BP1 illustrated in FIG. 14 inthat both ends of the light shielding member BP2 respectively extend tothe edges of the light shielding film BM illustrated in FIG. 15 .

In the modification examples illustrated in FIGS. 15 and 16 , both endsof the slit SLT5 communicate with the edges of the light shielding filmBM, as in the modification examples described with reference to FIGS. 8and 9 , so that a path where water, having entered the corner part BMc3of the light shielding film BM, bypasses can be blocked. Therefore,water, having entered a region surrounded by the slit SLT5 and the edgesof the light shielding film BM, can be prevented from reaching thedisplay section DP.

While an example in which slits SLT are respectively formed only in thefour corner parts BMc1, BMc2, BMc3, and BMc4 of the light shielding filmBM is illustrated in FIG. 10 , various modification examples can beapplied unless the circuit section CP and the light shielding member BPillustrated in FIG. 11 do not overlap each other in the thicknessdirection. In the example illustrated in FIG. 10 , for example, thecircuit section CP (see FIG. 11 ) is not formed in a region (i.e., aside) between the corner parts BMc1 and BMc2 of the light shielding filmBM. Therefore, the slit SLT formed in the corner part BMc1 and the slitSLT formed in the corner part BMc2 may communicate with each other. Inthis case, water entering the side BMs2 of the light shielding film BMcan be prevented from reaching the display section DP.

When a wiring for connecting the terminal TM1 and the circuit section CPillustrated in FIG. 11 needs to be formed in a region opposing thecorner parts BMc3 and BMC4 arranged on the side of the terminal sectionTM among the four corner parts BMc1, BMc2, BMc3, and BMc4 of the lightshielding film BM, the opening area of the slits SLT formed in thecorner parts BMc3 and BMc4 may be small. Alternatively, there is also amodification example in which if an arrangement space of the slit SLT isdifficult to be ensured in the corner parts BMc3 and BMc4, the slit SLTis not arranged in the corner parts BMc3 and BMc4 among the four cornerparts BMc1, BMc2, BMc3, and BMc4 of the light shielding film BM.

The light shielding member BP illustrated in FIG. 12 need not be coveredwith the insulating film OC2. Therefore, any one of the slits SLTillustrated in FIG. 6, 8 , or 9 can be formed in each of the four cornerparts OCc1, OCc2, OCc3, and OCc4 of the insulating film OC2 illustratedin FIG. 11 by combining a configuration of a display device LCD2 and theconfiguration of the display device LCD1 described with reference toFIGS. 5 to 9 , for example. In this case, if respective positions of thelight shielding member BP illustrated in FIG. 11 and the slit SLTillustrated in FIG. 6, 8 , or 9 overlap each other, a part of the lightshielding member BP is exposed from the insulating film OC2 in the slitSLT.

<Details-3 of Frame Section>

As an embodiment other than the display device LCD2 described withreference to FIGS. 10 to 16 , another technique for suppressing entranceof water from the periphery of an organic film formed on the side of thesubstrate 11 out of the substrates 11 and 12 illustrated in FIG. 4 willbe described.

FIG. 17 is a plan view on the side of a back surface of a CF substrateserving as a modification example of FIG. 10 . FIG. 18 is an enlargedsectional view taken along a line A-A illustrated in FIG. 17 .

A display device CLD3 illustrated in FIGS. 17 and 18 differs from thedisplay device LCD2 illustrated in FIGS. 10 and 12 in that a slit SLT6continuously surrounding a periphery of a display section DP of thesubstrate 11 is formed. The slit SLT6 is formed so as to penetrate alight shielding film BM in a thickness direction. The display deviceLCD3 differs from the display device LCD2 illustrated in FIGS. 10 and 12in that a light shielding member BP3 is formed in a region where theslit SLT6 is formed.

The display device LCD3 suppresses entrance of water by forming the slitSLT6 in the light shielding film BM serving as an organic film. Leakageof light is suppressed by forming the light shielding member BP3 in aportion where the slit SLT6 is formed. The light shielding member BP3 isformed of an inorganic material such as chromium or a chromium oxide.Even if the light shielding member BP3 is arranged in the portion wherethe slit SLT6 is formed, therefore, entrance of water can be suppressed.

As illustrated in FIG. 18 , the width of the light shielding member BP3is larger than the opening width of the slit SLT6. Therefore, both endportions of the light shielding member BP3 are covered with the lightshielding film BM. Thus, both end portions of the light shielding memberBP3 are covered with the light shielding member BM, so that leakage oflight can be reliably prevented.

In the display device LCD3, the light shielding member BP3 is formed onthe side of the substrate 11, so that the light shielding member BP isnot formed in the substrate 12 illustrated in FIGS. 3 and 4 . Therefore,a circuit section CP and the slit SLT6 may overlap each other, asillustrated in FIG. 17 , so that the slit SLT6 can be formed so as tocontinuously surround a periphery of the display section DP. Therefore,not only entrance of water into corner parts of the display section DP,but also entrance of water into each of the sides of the display sectionDP can be suppressed.

In the display device LCD3, the light shielding member BP need not beformed on the side of the substrate 12. Therefore, a configuration ofthe display device LCD3 illustrated in FIGS. 17 and 18 and theconfiguration of the display device LCD1 described with reference toFIGS. 5 to 9 can be easily applied in combination.

In the foregoing, the invention made by the inventors of the presentinvention has been concretely described based on the embodiments.However, it is needless to say that the present invention is not limitedto the foregoing embodiments and various modifications and alterationscan be made within the scope of the present invention. Although adisplay device using a liquid crystal layer as a display functionallayer is discussed in the above-described embodiment, for example, thepresent invention is not limited thereto. For example, theabove-described technique can also be applied to a frame section of adisplay device of a so-called an Organic Electro-Luminescence (EL) typeusing a light emitting element composed of an organic compound as adisplay functional layer.

In the category of the idea of the present invention, a person withordinary skill in the art can conceive various modified examples andrevised examples, and such modified examples and revised examples arealso deemed to belong to the scope of the present invention. Forexample, the examples obtained by appropriately making the additions,deletions or design changes of components or the additions, deletions orcondition changes of processes to respective embodiments described aboveby a person with ordinary skill in the art also belong to the scope ofthe present invention as long as they include the gist of the presentinvention.

The present invention is usable for a display device such as a liquidcrystal display and an electronic apparatus that incorporates thedisplay device.

What is claimed is:
 1. A display device including a display section anda frame section surrounding the display section, the display devicecomprising: a first substrate; a light shielding film provided on thefirst substrate; a second substrate opposed to the first substrate; aplurality of conductor patterns provided on the second substrate; and afirst organic film covering the conductor patterns, wherein a slit whichpenetrates the light shielding film in a thickness direction is formedin the light shielding film, and is disposed at a corner portion of thefirst substrate in a plan view, an edge of the light shielding film hasa first edge and a second edge extending in a direction crossing thefirst edge, the slit has a first slit extending along the first edge anda second slit extending along the second edge, one of the first slit andthe second slit is formed up to the edge of the light shielding film ina plan view, in the plan view, the light shielding film has a firstportion and a second portion, the first portion and the second portionare separated from each other by the first slit and the second slit. 2.The display device according to claim 1, wherein the second slit isformed up to the first edge in a plan view.
 3. The display deviceaccording to claim 1, wherein the first slit and the second slit areconnected to each other.
 4. The display device according to claim 1,wherein the light shielding film composed of an organic material.
 5. Thedisplay device according to claim 1, wherein the slit is formed only inthe corner portion.
 6. The display device according to claim 1, whereinthe first slit is formed up to the second edge in a plan view.
 7. Thedisplay device according to claim 6, wherein the second slit is formedup to the first edge in a plan view.
 8. The display device according toclaim 1, wherein an end portion of the first substrate has a first endportion and a second end portion extending in a direction crossing thefirst end portion, the frame section has a first virtual line extendingalong the first end portion and a second virtual line extending alongthe second end portion, the first virtual line and the second virtualline are extensions of contour lines of the display section, and thecorner portion is a region surrounded by the first virtual line, thesecond virtual line, the first end portion, and the second end portion.9. The display device according to claim 8, wherein the first edge andthe first end portion are aligned, and the second edge and the secondend portion are aligned.
 10. The display device according to claim 1,wherein one of the conductor patterns is disposed at a positionoverlapping the first slit and the second slit.
 11. The display deviceaccording to claim 10, wherein a width of the one of the conductorpatterns is larger than a width of the slit, in a plan view.